/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
* <p/>
* http://www.apache.org/licenses/LICENSE-2.0
* <p/>
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.cassandra.db;
import org.apache.cassandra.concurrent.Stage;
import org.apache.cassandra.concurrent.StageManager;
import org.apache.cassandra.config.ConfigurationException;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.db.migration.Migration;
import org.apache.cassandra.net.IVerbHandler;
import org.apache.cassandra.net.Message;
import org.apache.cassandra.service.MigrationManager;
import org.apache.cassandra.utils.UUIDGen;
import org.apache.cassandra.utils.WrappedRunnable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOError;
import java.io.IOException;
import java.util.Collection;
import java.util.UUID;
public class DefinitionsUpdateResponseVerbHandler implements IVerbHandler
{
private static final Logger logger = LoggerFactory.getLogger(DefinitionsUpdateResponseVerbHandler.class);
/** someone sent me their data definitions */
public void doVerb(final Message message)
{
try
{
// these are the serialized row mutations that I must apply.
// check versions at every step along the way to make sure migrations are not applied out of order.
Collection<Column> cols = MigrationManager.makeColumns(message);
for (Column col : cols)
{
final UUID version = UUIDGen.getUUID(col.name());
if (version.timestamp() > DatabaseDescriptor.getDefsVersion().timestamp())
{
final Migration m = Migration.deserialize(col.value());
assert m.getVersion().equals(version);
StageManager.getStage(Stage.MIGRATION).submit(new WrappedRunnable()
{
@Override
protected void runMayThrow() throws Exception
{
// check to make sure the current version is before this one.
if (DatabaseDescriptor.getDefsVersion().timestamp() == version.timestamp())
logger.debug("Not appling (equal) " + version.toString());
else if (DatabaseDescriptor.getDefsVersion().timestamp() > version.timestamp())
logger.debug("Not applying (before)" + version.toString());
else
{
logger.debug("Applying {} from {}", m.getClass().getSimpleName(), message.getFrom());
try
{
m.apply();
}
catch (ConfigurationException ex)
{
// Trying to apply the same migration twice. This happens as a result of gossip.
logger.debug("Migration not applied " + ex.getMessage());
}
}
}
});
}
}
}
catch (IOException ex)
{
throw new IOError(ex);
}
}
}